A Few Days to the Launch of the Mission to Save the Swift Space Telescope from Atmospheric Reentry
In the past, there has been widespread discussion about the possibility of carrying out a mission to "save" the Hubble Space Telescope, after the end of the Space Shuttle's operational life (which had been used to launch it into orbit and had executed repair and upgrade missions). In the coming days, there will be another mission aimed at extending the operational life of the Swift Space Telescope (also known as the Neil Gehrels Swift Observatory) and avoiding its reentry into the Earth's atmosphere over the coming months.
The mission launch is scheduled around 11:00 AM on June 27 (Italian time) using a Northrop Grumman Pegasus XL launch vehicle. This approach uses a different launch system compared to other vehicles, detaching from a flying airplane to continue the ascent with rocket thrusters (similar to the failed Virgin Orbit, although Northrop Grumman's solution came to market much earlier). It is a three-stage vehicle with limited payload capacity, but sufficient to carry a satellite necessary for the mission dedicated to the Swift Space Telescope.
The Mission to Save the Swift Space Telescope
As explained by NASA, satellites in low Earth orbit experience atmospheric drag from the Earth's atmosphere. Thanks to propulsion systems, vehicles can regain altitude, but this is not always possible. Recent solar storms have expanded the upper atmosphere, increasing drag and worsening the situation for the Swift Space Telescope, which has begun to lose altitude faster than expected.
The space agency had to act quickly, awarding a contract to Katalyst in the second half of last year to create the LINK support satellite (weighing 400 kg). This vehicle will need to reach the space telescope and raise its orbit again using its own thrusters. The goal is to reach at least 300 kilometers in altitude to extend its operational life. To do this, it will use three robotic arms that will connect to the back of the observatory to then "gently push" it upwards.
The mission will have relatively lengthy timelines. After launch, it will take two weeks to perform the initial checks on the LINK satellite. Once the satellite is deemed healthy, up to three weeks will be needed for the first close-range analyses and approximately two weeks to proceed with capturing the telescope. The orbital raising will take three months, and at that point, the mission control center will verify that everything has proceeded as planned before returning to collect scientific data.
The space agency had also considered bringing the Swift Space Telescope back into the atmosphere, risking losing an interesting tool for sky observation. After all, this was a vehicle launched in 2004 and well beyond its initially estimated operational life. However, "risking" damaging such a satellite is also seen as useful for future, more complex missions that could have more ambitious objectives (like Hubble).
Once integrated with the Pegasus XL launch vehicle, it was secured to the bottom of the fuselage of the Northrop Grumman L-1011 airplane, which transported it from the Wallops Flight Facility in Virginia to the Kwajalein Atoll (Marshall Islands). Here, in the coming days, the airplane will take off with the vehicle, launching the mission.
The Swift Space Telescope enables the study of GRBs (gamma-ray bursts). For this reason, it is equipped with various instruments that allow scientists to be "alerted" quickly when a GRB is spotted to carry out more accurate analyses with other scientific instruments. This space observatory has scientific instruments that observe in X-rays and in the ultraviolet/optical spectrum.